Technical data

Network configuration
3.1 Configuring electrical networks
PROFIBUS Network Manual
44 System Manual, Edition 04/2009, C79000-G8976-C124-03
Table 3- 4 Weighting for segments at 1.5 Mbps
Product name
RS-485 bus terminal with 3.0 m long spur line
(order no. 6GK1 5000BA00, version 2)
1.5
RS-485 bus terminal with 1.5 m long spur line, with PG interface
(order no. 6GK1 500 0AD00 , version 2)
1.5
Bus connector with axial cable outlet (order no.: 6GK1 500-0EA02)
Bus connector with axial cable outlet for FastConnect system
(order no.: 6GK1 500-0FC10)
Bus connector with 90° cable outlet (order no.: 6ES7 972-0BA12-0XA0)
Bus connector with 90° cable outlet with PG interface
(order no.: 6ES7 972-0BB12-0XA0)
Bus connector with 90° cable outlet for FastConnect system
(order no.: 6ES7 972-0BA51-0XA0)
Bus connector with 90° cable outlet with PG interface
(order no.: 6ES7 972-0BB51-0XA0)
Bus connector with 35° cable outlet (order no.: 6ES7 972-0BA41-0XA0)
Bus connector with 35° cable outlet with PG interface
(order no.: 6ES7 972-0BB41-0XA0)
0.1
Bus terminal 12M (order no. 6GK1 500-0AA10) 0.1
RS485 repeater (attachment of bus segments) (order no. 6ES7 972-0AA01-0XA0) 0.1
Active RS-485 PROFIBUS terminator
(order no. 6ES7 972-0DA00-0AA0)
0.1
SIMATIC S5/S7 connecting cable for 12 Mbps PG attachment to PROFIBUS DP
(order no.: 6ES7 901-4BD00- 0XA0 )
0.5
Rules
At a transmission speed of 1.5 Mbps, the following rules apply to the permitted number of
nodes and their distribution/arrangement in a SIMATIC NET PROFIBUS segment:
● The maximum permitted number of nodes in any segment is 32.
● The sum of the weightings of all the connection elements in a segment must be ≤ 25.
● The rules for the distances between adjacent connection elements are as follows
(distance in this case is the length of the bus cable):
– If the distance between adjacent connection elements is greater than 10 m, the
weighting of the connection elements can be ignored.
– If the distance between adjacent connections elements is greater than the sum of the
two weighting values of the elements in meters, the arrangement is not critical and no
additional conditions need to be taken into account. The weighting value of the PG
connecting cable, SIMATIC S5/S7 connecting cable 12 Mbaud must be added to the
value of the corresponding connection element.
– If the minimum clearance described above is not kept to, a group is formed and the
following additional conditions must be adhered to:
Attachment elements can be arranged as close to each other as required providing
the sum of their weighting values does not exceed the value 5.
The distance in meters between two adjacent groups must be at least as large as the
sum of the weighting values of the two groups.